By any standard, General Motors (NYSE: GM) had a pretty good year in 2010. The company got back on solid financial ground, it got a (we hope) real non-interim CEO, it launched several impressive new products, and it posted solid growth in its two biggest markets.

For Toyota (NYSE: TM), on the other hand, 2010 seemed like a year to forget. The company saw its U.S. sales fall sharply, lagged GM and others in China, faced big challenges in Japan, and suffered through a global PR nightmare and a long list of expensive recalls.

Yet Toyota still led GM in global sales when all was said and done. The company's 30,000-vehicle lead wasn't much in context -- each automaker booked well over 8 million sales -- but it was enough for the Japanese giant to retain the global sales crown for the third straight year.

But if GM couldn't regain the lead when Toyota was down in 2010, does it have a chance in 2011?

Roughly equal shares of the pie
As you might expect, GM's PR folks said the automaker doesn't care whether it's No. 1 or not. And it's true that GM's current management has been at pains to emphasize measures such as profitability over market share and sales totals, a welcome change from the company's sales-at-any-price past.

But sales leadership is still an important symbol, and GM is going to look to take its recovery to the next level in 2011. Although several major new products are still a year or more away, big things are expected from new global marketing chief Joel Ewanick, starting with what is rumored to be a massive ad blitz during this weekend's Super Bowl.  

Certainly, the General's lead in the U.S. seems safe for the moment, with Toyota having dropped to third place behind Ford (NYSE: F) -- something that shows no sign of changing anytime soon. And GM's outsized lead in China seems more likely to be threatened by Volkswagen than by Toyota, which, like rival Honda (NYSE: HMC), is well behind both in the local sales rankings.

But Toyota is the undisputed king of its home market, and its small-car subsidiary Daihatsu has a strong emerging-markets presence of its own, with plants in places such as Indonesia and Venezuela. Auto sales in Japan have slumped recently but are expected to pick up as the year goes on, and Toyota is likely to be the biggest beneficiary.

But really, both of these companies have the same basic problem, and the first one to solve it is likely to be 2011's global sales leader.

It's the product, stupid
Economic cycles rise and fall, and different markets have different strengths and priorities, but ultimately, automakers thrive or dive on the strength of their product line. A company with fresh new products that excite customers will see sales (and usually, profits) go up -- and conversely, a company with a product line that's starting to look a little stale will generally see sales sag.

Ford made a point of investing heavily in new products during the worst of the economic downturn, and it paid off with big sales gains for the Blue Oval during 2010. GM and Toyota, on the other hand, are offering product lines that are starting to look a little dated. A recent report from Edmunds pointed out that many car-shoppers have little product loyalty, shop mainly on features, and will tend to dismiss offerings that lack the latest technology -- a description that applies to much of Toyota's product line, at least in the U.S., as well as several key GM offerings.

As I've noted elsewhere, GM is well on the road to catching up, but the heart of GM's new-product offensive is still a year or two (or three) away. Toyota, on the other hand, has promised 11 new or updated products for the U.S. in 2011 -- and when we look back in a year's time, those new models could turn out to be the difference.

Add GM and Toyota to My Watchlist today to stay on top of all of our Foolish coverage as this global war of giants unfolds.

Fool contributor John Rosevear owns shares of GM and Ford. GM is a Motley Fool Inside Value selection. Ford is a Motley Fool Stock Advisor pick. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.